Hashimoto’s thyroiditis is a chronic inflammatory autoimmune disease where the thyroid gland is attacked by autoantibodies and is gradually destroyed. Hashimoto’s thyroiditis, which usually develops in adulthood, is the commonest type of hypothyroidism.

Environmental factors, other autoimmune disorders, aging and genetics are thought to be the cause of Hashimoto’s Thyroiditis. A triggering event added to an existing hereditary predisposition can cause an autoimmune disorder in which the body mistakes its own thyroid cells as foreign cells and therefore destroys them. The more the thyroid’s tissue gets damaged, the more the body’s ability to produce the thyroid hormone decreases. In Hashimoto’s Thyroiditis, some patients may have goiters, which means that they have a growth in their thyroid gland, and some patients may have atrophy, which means that their thyroid gland has decreased in size due to the destruction of its tissue.

Risk Factors
A significant risk factor for Hashimoto’s thyroiditis is having another autoimmune disease, like type 1 diabetes, celiac disease, vitiligo and alopecia. A family history of other thyroid disorders is also a risk factor for this disease. The environmental risk factors of Hashimoto’s thyroiditis include high iodine intake, various infectious diseases, certain drugs, and selenium deficiency.

Symptoms
Hashimoto’s Thyroid is more prominent in women than in men. The common symptoms of Hashimoto’s thyroiditis include:

• Weight Gain
• Fatigue
• Pale/puffy Face
• Muscle/joint pain
• Dry/thinning hair
• Constipation
• A slowed heart rate

In some cases of Hashimoto’s thyroiditis, the thyroid gland may enlarge and become lobulated, but sometimes the changes to the thyroid gland may not be visible.

Pathology and Diagnosis
When the thyroid’s tissue gets damaged the body’s ability to produce thyroid decreases. T3 and T4 – the thyroid hormone levels – dip due to this, and this cause the parathyroid to send out thyroid stimulating hormone (TSH) to the thyroid gland. Although, as the thyroid gland is injured, it cannot respond to TSH and is unable to manufacture more thyroid. Due to this, the TSH levels are high and the T3 and T4 levels are low.

Therefore, testing for the levels of TSH, T3 and T4 can help in giving an accurate diagnosis of Hashimoto’s Thyroiditis. The diagnosis of Hashimoto’s Thyroiditis is also done by the identifying a raised level of anti-thyroid peroxidase antibodies.   

Treatment
Replacement agents for thyroid hormone, like levothyroxine, desiccated thyroid extract or triiodothyronine are used to treat Hashimoto’s thyroiditis. Generally, one tablet everyday normalizes thyroid hormone levels.